Staircase unit and mould for making said unit

ABSTRACT

The present invention relates to mould means for making a precast staircase unit comprising an integral assembly of two staircase flights, a half-landing and a supporting spine wall.

United States Patent Inventors John Desmond Peacock Gerrards Cross; Ian Sim Wilson, Oakley Green, near Windsor, England Appl. No. 730,347 Filed May 20, 1968 Patented Mar. 2, 1971 Assignee Concrete Limited Priority Apr. 26, 1968 Great Britain 20069/68 STAIRCASE UNIT AND MOULD FOR MAKING SAID UNIT 8 Claims, 11 Drawing Figs.

US. Cl 249/14, 25/118, 52/190 Int. Cl. B28b 7/22 Field of Search 249/ 14; 52/190; 25/1 185 [56] References Cited UNITED STATES PATENTS 2,489,607 11/1949 Alexander 249/14 3,281,110 10/1966 Lister 249/14 3,340,926 9/ 1967 Sylvester 249/155X FOREIGN PATENTS 138,851 6/1961 U.S.S.R. 249/14 OTHER REFERENCES 1263570 3-1968 W. Germany Lotter Hos. Pre Fabricated Stair Flights Cl. 52 Sub 190 Primary Examiner-Charles W. Lanham Assistant Examiner--Ben D. Tobor Attorney-Lawrence E. Laubscher ABSTRACT: The present invention relates to mould means for making a precast staircase unit comprising an integral assembly of two staircase flights, a half-landing and a supporting spine wall.

PATENTED m 215?! $567,172

SHEET U U? 5 |NVENTOR5 ATTORNEY STAIRCASE UNIT AND MOULD FOR MAKING SAID UNIT The present invention is concerned with a precast staircase unit and a mould for making said unit. The invention finds employment in the construction of buildings comprising precast concrete elements. I

According to the present invention in one aspect, there is provided a precast staircase unit comprising first and second stair flights, a landing portion between the top of one flight and the foot of the other flight, and a spine wall interconnecting the two flights.

According to the present invention in another aspect, there is provided a mould for making a precast staircase unit, said mould comprising first and second mould cavities for forming first and second stair flights, a third mould cavity forming a landing portion between the top of one flight and the foot of the other flight, and a fourth mould cavity for forming a spine wall interconnecting the two flights.

The invention has the significant advantage that the elements comprising the stair flights, landing portion and spine wall are formed integrally with each other and make up the complete unit which can be erected, as a complete unit, on site. Such an arrangement is significantly less expensive and significantly less time consuming in erection than an arrangement in which the above elements are precast separately, have to be separately transported to the site and then connected together on site.

The present invention will be more readily understood from the following description, given by way of example only, reference being made to the accompanying drawings in which:

FIG. I is a plan view of a precast staircase unit of the invention;

FIG. 2 is a sectional view along the line. II-II of FIG. 1.

FIG. 3 is a sectional view along the line I-II-III-of FIG. 1;

FIG. 4 is a schematic isometric view showing the basic parts of a mould for making the unit of FIGS. 1 to 3;

FIG. 5 is a plan view of a portion of the mould;

FIG. 6 is a view in the direction of arrow B of FIG. 5;

FIG. 7 is a view in the direction of arrow C of FIG. 5;

FIG. 8 is a plan view of the mould;

FIG. 9 is a side view showing the means for moving one of the movable shutters of the spine wall mould cavity;

FIG. 10 is a plan view of one of the shutters for the mould cavity which forms the first stair flight; and

FIG. 11 is a view in the direction of arrow D of FIG. 10.

Turning to FIGS. 1 to 3, there is shown a staircase unit 10 comprising first and second staircase flights 11,12 respectively, a landing portion 13 between the top of flight 11 and the foot of flight 12, and a spine wall 14 interconnecting the two flights. The unit is ascended in the direction illustrated by the arrow A in FIG. 1. With particular reference to FIG. 3, the landing portion 13 is shown having a step 15 between a lower part of the landing portion leading from the top of flight 11 and an upper part of the landing portion leading to the foot of A number of legs extend upwardly from the baseplate and support a lower fixed section of the mould. A part of one of these legs is shown at 17 in FIG. 4. The said lower fixed section is shown at 18 and comprises a flat plate which defines a part of the base of the mould cavity for the spine wall. As viewed in FIG. 4, the left-hand end of the section 18 is shaped to the contour of the stairs of the first flight 11. The mould cavity for the flight 11 is indicated at 20. The mould shutter 21 which forms the stairs is fixed to the plate. of section 18 and extends between that plate to the baseplate which it engages. The shutter 21 extends between locations marked 22 and 23. The position of location 23 will be appreciated from FIG. 5. Extending outwardly of the location 23, the section 18 has a shutter portion 24 which forms the riser of the step 15 in the landing portion.

Cooperating with the shutter 21 and bounding the cavity 20 is a mould shutter 25 which is movable towards and away from the shutter 21 by means to be described. When in moulding position, the shutter 25 is bolted to the shutter 21 at points indicated at 26 and extends downwardly to engage the baseplate. The shutter 25 extends downwardly and is secured to a plate 28 which lies at the same level as the plate of the section 18. The plate 28 defines the other part of the base of the mould cavity for the spine wall; it will be remembered that the remainder of the base of that mould cavity is defined by the plate of the section 18. Items 27 are fixed side shutters for the spine wall mould cavity and are secured to plate 28.

The mould cavity for the landing portion at the top of stair flight 11 is shown at 30. This cavity is bounded by a mould shutter 31 which forms the lower surface of the said landing portion. The shutter 31 has at the top thereof a stiffener 32.

When the mould is set up for casting, the shutter 25 bears against portion 33 of shutter 31. The shutter 31 extends to a height level with the top of framework 27. The top of shutter 21 is level with the top of stiffener 32. End plate 34 closes the end of cavity 30.- Props, not shown, may extend from the flight 12. It is however to be understood that the invention shown in FIGS. 1 to 3 and reference will first be paid to FIG. 4

from which an understanding of the basic parts of the mould will be obtained.

Because of floor unevenness, the mould shown generally at 16 in FIG. 4 rests on a baseplate not shown in FIG. 1 (but see FIG. 11). If the floor of the casting area were sufficiently even, or if such floor were given a special surface, it may be possible to dispense with the baseplate.

ground into engagement with shutter 31 to keep it in position and to prevent bulging thereof. The top of cavity 30 is open.

The framework 27 has been mentioned as providing two fixed side shutters for the spine wall mould cavity. A further fixed side shutter for this cavity is shown at 35 secured to the plate of section 18. Two movable side shutters for this cavity are shown at 36 and 37. Each of the side shutters for the spine wall mould cavity are of L-shaped cross section. The means for moving the shutters 36, 37 is described hereinafter.

The mould cavity for casting. the second stair flight 12 is shown at 38, and themould cavity for casting the landing portion at the foot of stairflight 12 is shown at 40. The cavities 38 and 40 are bounded by removable shutters 41 and 42. The shutter 41 forms the stairs of the flight 12 and also forms the upper surface of the landing portion at the foot of stair flight 12. The shutter 41 preferably has a stiffener plate (not shown) at the top and bottom thereof extending the length of the shutter and extending away from the cavity 38. The top one of these 'stiffeners may be engageable by means for lifting the shutter 41 away from the mould. The staircase forming portion of shutter 41 rests on shutters 35 and 36, and the shutter portion bounding the cavity 40 rests on shutter portion 24.

' The portion of shutter 41 which bounds the cavity 40 is higher than the portion which bounds the cavity 38 by the height of the shutter 35. Thus that portion of shutter 4 which bounds the cavity 40 abuts the end of shutter 35 and rests on and projects from the plate of section 18.

To the exterior of the shutter 42 is secured a bar 43 which serves to connect the shutter 42, and hence the shutter 41 which is indirectly secured to the shutter 42, to the remainder of the mould. One end of the bar 43 is connected to the stiffener 32 at 44. The other end of the bar 43 is secured to the plate of section 18 (see FIG. 8).

The cavity 38 is closed by an end plate 45 which is bolted to the shutters 41 and 42. The cavity 40 is closed by an end plate 46 which is also bolted to these two shutters.

Extending from the end plate 46 and secured thereto is a plate 47 on which rests the'shutter 42. The base of shutter 42 is at the same level as the top of the spine wall side shutters. It will therefore be appreciated that the edge 48 of shutter 42 is at the same level as the edge 50 of shutter 31, and that these edges coincide with the edges 51 and 52 respectively of the step 15 (see FIG. 3). There is, of course, an end shutter between the end shutters 34 and 46 to prevent concrete from escaping from the space between the cavities 30 and 40, in which space the step 15 will be formed.

The mould is closed by a shutter 53 which is fixed to the shutter portion 24 and extends downwardly from the shutter portion 24 and which rests on the baseplate. Props, not shown, may extend from the ground into engagement with shutter 53 to keep it in position and to prevent bulging thereof. It has been mentioned that the riser of step 15 is inclined to the vertical and this is achieved by inclining'the shutter portion 24. The manner in which this is done will be seen from FIGS. to 7 which show the shutter portion 24 and a part of the plate of section 18 adjacent the portion 24. In FIGS. 5 to 7, a side edge of the plate of section 18 is shown at 54 and the shutter 21 is shown terminating at line 55 which contains location 23 (see FIG. 4). The line 55 is level with the inner end 56 of shutter portion 24 and end 56 is level with the inside surface of shutter 35. The shutter portion 24 is so arranged that its side 57 is above its side 58 and it is this arrangement which results in the riser of step being inclined to the vertical. It will be realized that side 58 of shutter portion 24 is at the'same height as the plate of section 15; to accommodate the inclination of the shutter portion 24, the shutter 53 extends to a slightly greater height than shutter 21.

The following is the procedure when casting a staircase unit using the mould 16. The mould is first set up as seen in FIG. 4

but with the shutters 41 and 42 and end plates 45 and 46 removed. Concrete is then poured into cavities 20 and 30 to the level of the plate of section 18. The shutters 41, 42 and end plates 45, 46 are then put in place and concrete is poured onto the plate of section 18 and onto plate 28 to the level of the top of the shutters of the spine wall mould cavity, i.e. to the top of framework 27 and side shutters 35, 36 and 37. Concrete is also poured into cavities 38 and 40 and into the cavity between cavities 30 and 40 to form the step 15. The mould may be vibrated to settle and compact the concrete.

Certain details of the mould 16 not shown in FIGS. 4 to 7 will now be described with reference to FIGS. 8 to 1].

Turning to FIG. 8, there is shown the connection at 60 between the bar 43 and the plate of section 18, which connection was not visible in FlG. 4. It has been said that the side shutters 36 and 37 are movable and the means for moving them comprises pairs of rams shown at 61 for shutter 36 and 62 for shutter 37. The shutters 36 and 37 are movable in exactly the same manner, and accordingly only the means for moving shutter 37 will be described, reference being made to FIG. 9. This FlG. only shown the connection between one ram 62 and the shutter 37 because the connections as between rams 62 and shutter 37 are identical.

Turning to FIG. 9, the shutter 37 is slidable relative to the plate of section 18. Bolted to the rear of shutter 37 is a bracket 63 having a forked end 64. The bracket 63 is pivotally connected at 65 to a mounting plate 66 fast with the underside of the plate of section 18. Also fast with the underside of this plate is a further mounting plate 67. The cylinder of the ram 62 is pivotally connected at 68 to the bracket 67; the piston rod 70 of the ram is pivotally connected at 71 to the forked end 44 of the bracket 63. It will be appreciated that introduction and expulsion of pressure medium into and out of the ram cylinder will cause inward and outward movement of the shutter 37.

It will be recalled that mention has been made of the shutter 25 being movable. The manner in which such movement is achieved is described with reference to FIGS. 10 and 11; these FlGS. being plan and side views respectively of the shutter 25.

Turning particularly to FIG. 11, the shutter 25 has connected to its base a bracket 72 which is pivotally connected at 73 to a further bracket 74 fast with one (75) of a number of bearer members which support the baseplate previously referred to and identified at 76. Secured to the ground is a mounting 77 to which. is pivotally connected the cylinder of a ram 78; the piston rod 80 of this ram is pivotally connected at 81 to the shutter 25. It will be appreciated that introduction and expulsion of pressure medium into and' out of the ram cylinder will cause inward and outward movement of the shutter 25.

It will be appreciated that the staircase unit will need to have castellations or recesses formed in its end faces to ensure proper connection with the other elements of the building of which the unit will form a part. These castellations or recesses are formed by suitably shaped and arranged side and end shutters.

To remove a cast unit from the mould 16, the mould is suitably stripped and the unit lifted by a lifting device designed for the purpose.

We claim:

1. A mould for making a precast staircase unit, said mould comprising means defining first and second mould cavities for forming first and second stair flights, respectively, a third mould cavity for forming a landing portion between the top of one flight and the foot of the other flight, and a fourth mould cavity for forming a spine wall interconnecting the two flight.

' 2. A mould according to claim 1, wherein the means defining said third mould cavity includes shutter means for forming a step in the landing portion.

3. A mould according to claim 1,.wherein the means defining said fourth mould cavity has a side shutter mounted for inward and outward movement.

4. A mould according to claim 3 including drive means for causing said movement of the side shutter of the fourth mould cavity.

5. A mould as defined in claim 1, and further including a generally horizontal baseplate (76), said means (21, 25) defining one (20) of said first and second mould cavities being generally vertical and extending upwardly from said baseplate, said means defining said fourth mould cavity extending generally parallel with said baseplate and including a pair of coplanar horizontal plates (18, 28), and said means (41, 42) defining the other (38) of said first and-second mould cavities being generally vertical and extending upwardly from said means defining said fourth cavity.

6. A mould as defined in claim 5, wherein said means defining said one of first and second cavities includes first and second vertically arranged shutters (21, 25 connected at their upper ends with said pair of plates (18, 28), respectively; and further including means connecting one (25) of said shutters and the plate (28) connected thereto for movement alternately toward and away from the other (21) of said shutters and the plate (18) connected thereto.

7. Apparatus as defined in claim 6, wherein said means connecting said one shutter and the associated plate for movement relative to the other of said shutters and the associated plate comprises pivot means (73) pivotally connecting said movable shutter at its lower end with said baseplate (76) for movement about a horizontal pivot axis.

8. Apparatus as defined in claim 6, and further including drive means (78) for effecting movement of the movable shutter and the plate associated therewith relative to the other of said shutters and the plate associated therewith, respective- 

1. A mould for making a precast staircase unit, said mould comprising means defining first and second mould cavities for forming first and second stair flights, respectively, a third mould cavity for forming a landing portion between the top of one flight and the foot of the other flight, and a fourth mould cavity for forming a spine wall interconnecting the two flight.
 2. A mould according to claim 1, wherein the means defining said third mould cavity includes shutter means for forming a step in the landing portion.
 3. A mould according to claim 1, wherein the means defining said fourth mould cavity has a side shutter mounted for inward and outward movement.
 4. A mould according to claim 3 including drive means for causing said movement of the side shutter of the fourth mould cavity.
 5. A mould as defined in claim 1, and further including a generally horizontal baseplate (76), said means (21, 25) defining one (20) of said first and second mould cavities being generally vertical and extending upwardly from said baseplate, said means defining said fourth mould cavity extending generally parallel with said baseplate and including a pair of coplanar horizontal plates (18, 28), and said means (41, 42) defining the other (38) of said first and second mould cavities being generally vertical and extending upwardly from said means defining Said fourth cavity.
 6. A mould as defined in claim 5, wherein said means defining said one of first and second cavities includes first and second vertically arranged shutters (21, 25) connected at their upper ends with said pair of plates (18, 28), respectively; and further including means connecting one (25) of said shutters and the plate (28) connected thereto for movement alternately toward and away from the other (21) of said shutters and the plate (18) connected thereto.
 7. Apparatus as defined in claim 6, wherein said means connecting said one shutter and the associated plate for movement relative to the other of said shutters and the associated plate comprises pivot means (73) pivotally connecting said movable shutter at its lower end with said baseplate (76) for movement about a horizontal pivot axis.
 8. Apparatus as defined in claim 6, and further including drive means (78) for effecting movement of the movable shutter and the plate associated therewith relative to the other of said shutters and the plate associated therewith, respectively. 